You know something's wrong in the increasingly bizarre world of US Republican politics when one of its shrillest, more extreme voices starts warning about 'self-promoting charlatans'. In a recent Time magazine debate about where conservatism was going in America, Ann Coulter warned her fellow Republicans against adopting the 'mob characteristics of the left' - a trend that included 'a susceptibility to self-promoting charlatans more interested in getting a gig on Fox News than saving the country'. No one, of course, has ever accused Coulter - a hectoring television presence and a self-styled hard-right author and commentator - of self-promotion. From the outside, such contradictions appear to highlight the troubles faced by Republicans. On paper, a worthy and presentable candidate would give US President Barack Obama a serious run for his money come November. Yet, remarkably, it is far from clear whether an embattled Republican establishment is going to be able to pull that off. Mitt Romney, their most credible, if hardly compelling, front runner is struggling to finish off an insurgent primary field that has seen late bursts from former House Speaker Newt 'Fly me to the Moon' Gingrich and arch social conservative Rick Santorum. 'I don't recognise my own party any more,' one Republican lobbyist told me this weekend. 'Some days I wake up, scan the headlines, and tell myself that the lunatics have really taken over the asylum.' Could it be, though, the primary debacle is revealing that Republicans are victims of their own propaganda successes? For a few years now, it has been apparent that the dominance of right-wing talk radio and Fox News television has created a vast echo chamber where skilled policymaking and moderation is, at times, buried. The points go to those who can screech the loudest, without ever exposing them to real scrutiny. It has, of course, taken lumps out of Obama's appeal, propagating still-lingering myths about his birthplace, his 'palling around' with terrorists and his so-called 'socialism'. Obama undoubtedly faces a stubborn minority who cannot accept him as president. Yet, propaganda is acidic stuff, frequently damaging the originators who handle it. In this case, we can see some Republicans who are attempting to grace the national stage struggle beyond the comfort of their own airwaves. Those pressures will magnify many times over as the campaign proper heats up towards November. Old-time Republicans know that they've never won with an extremist candidate, and many still point to Lyndon Johnson's landslide over Barry Goldwater in 1964. And if the axis of US politics has tilted further right over the years, the brutal art of election victories remains occupation of that centre. Ultimately, warts-and-all American democracy is supposed to offer eternal renewal, whatever periods of excess have just passed. Perhaps, then, we are witnessing some kind of internal Republican renewal. Their problem is, they just might have to lose an election to pull it off. Chief Asia correspondent Greg Torode covered the US presidential elections in 2000 and 2008.